Crowley will only pay 25 caps for any killing method other than a head shot, but you can lie about the act and get the full price by passing a somewhat difficult speech check. This does not apply to Tenpenny; he must be shot in the head by you to get the full reward, since word of his death would spread rather quickly.

Bribing or passing a speech check with any of the named non-player characters (excluding Charon) in Underworld – Ahzrukhal, Carol, Doctor Barrows, Winthrop, Patchwork, Tulip, or Quinn – will raise doubts about the targets' bigotry. Under questioning, Crowley will admit that he actually wants a special key from each target except Tenpenny. He still wants Tenpenny killed with a shot to the head. Instead of 100 caps per headshot, he will sweeten the deal by offering 100 caps up front plus an additional 100 caps for each key. Mister Crowley's objective is the suit of T-51b power armor still stored at Fort Constantine. You can learn about Fort Constantine and the power armor from Crowley (with a speech check). Other than the additional reward, the conditions of the quest do not change by learning this.

The keys can be obtained by Speech checks, pickpocketing, or by looting the key from the owner's corpse. They may be collected in any order and can be delivered to Crowley one at a time or all at once.

Cherry will retrieve the key if the player passes a Speech check and agrees to take her to Rivet City. The Speech check option appears only once. If you reject taking her to Rivet City you won't get the chance a second time.

With a successful Speech check, Dukov can be intimidated into giving up the key. However, this speech check is very hard to pass, even with a Speech skill of 100.

With a Speech success, Dave will accept the player as a "Wasteland Ambassador" and present his key as a gift. He will also give you the key if you pass another speech check that is given if you failed the ambassador one.

Kill Allistair Tenpenny and give Mister Crowley all three keys to collect your reward. He will then proceed to Fort Constantine to retrieve the armor. He will return to Underworld after a few days (provided he did not get killed in the Wasteland). At this point you can kill him, which will turn all ghouls in Underworld hostile, or use reverse-pickpocketing in order to obtain the armor (he will be wearing it).

Reverse-pickpocketing will be difficult, because the armor has a DR of 50, one of the highest in the game.

Crowley may get stuck in bomb storage, even if he had all the keys. You need 100 lockpick skill to open the door.

Using the mesmetron (if successful) will turn him hostile, but everyone else will turn on him and kill him. This way, you can loot the armor off his body without angering the Underworld residents.

Proceed to Fort Constantine after obtaining the keys. Fort Constantine is located near the northern edge of the map, east-northeast of SatCom Array NW-05a and southeast of the Train Tunnel if The Pitt is installed. When you arrive at the fort you will encounter some Brotherhood of Steel Outcasts fighting protectrons and Mister Gutsies. Go to the small house labeled "CO Quarters," located downhill from Bomb Storage, and head downstairs. In the basement you will find a dead wastelander by an open safe. The door by the safe requires Strayer's key, and allows you access to the Launch Control Bunker. You can also grab the "Bobblehead - Big Guns" from the safe while you're there. Continue down the stairs towards Bomb Storage; you gain access here with Dukov's key. Inside the Bomb Storage facility, you will find Tara's body in front of a locked door. Open the door with Dave's key, proceed through the next door, disable the stasis field and take the T-51b power armor and T-51b power helmet.

There is a warhead storage key on Tara's body. It unlocks a door that's just up a set of steps from here. This leads to a large room where nuclear warheads are stored, and the area is consequently highly radioactive. This key also opens either of the Very Hard locked doors topside that lead to the Bomb Storage facility.

If you choose this solution, Mister Crowley can still be found in Carol's Place in the Underworld. He does not become hostile, but refuses to interact with the PC anymore, only repeating his line: "You stole what was rightfully mine..."

Kill Allistair Tenpenny and give Mister Crowley all three keys to collect your reward, then follow Crowley on his long journey to Fort Constantine. He will require a lot of protection from enemies in the Wasteland or else he will die along the way. Crowley will become hostile upon reaching Fort Constantine, at which point you can kill him to retrieve the keys.

If you don't want to follow Crowley, you can give him the keys and pickpocket them back, and then go to Fort Constantine. First open all the doors using the keys, but don't grab the armor, then give Crowley the keys to get the reward, then fast travel back and grab the armor. Additionally you can simply follow him into the lobby of the museum and kill him there (you will not lose any Karma).

If you have Broken Steel installed, Crowley will glitch outside of the Museum of History and get stuck in a pillar after you give him the keys. You can fix this problem by waiting by the entrance and skipping 2 in-game hours. Crowley should appear at the entrance and proceed to Fort Constantine. If you have the Point Lookout add-on, then you can also fix this problem if you exit Underworld following Mr. Crowley with the double-barrel shotgun equipped and drawn, then when you arrive in the lobby, he will be there running towards the entrance to the Museum. You have to do the same when exiting the Museum. This may work with other weapons too (though it does not work with all weapons).

Taking the T-51b power armor makes Crowley say, "You stole what was rightfully mine! Get lost."

Giving the keys to Mr. Crowley and then successfully pickpocketing them from him also makes him say this.

Killing Crowley anywhere other than Underworld will not make the residents of Underworld hostile, nor will killing him quickly or silently. If the quest is completed by giving Crowley the keys, the earliest way he can be safely killed (if the plan is to take the keys from his corpse) is in the museum entrance (between Underworld and the outside). This will not work, however, if Broken Steel is installed, due to the presence of ghouls around the Amazing Aqua Cura stand (assuming Take it Back! has been completed).

Encountering Crowley on his way back to Underworld from Fort Constantine makes him give another thanks and ask about his new armor.

If Tenpenny`s counter-offer to kill Mister Crowley is accepted and Crowley is killed by use of the Sandman perk, it does not count due to not detecting the Sandman kill.

Crowley's trip from Underworld to Fort Constantine is scripted, so if he is given the keys then acquires the T-51b power armor anyway (via either method detailed above), he will still eventually show up and be hostile as noted.

Placing mines in the power armor room to kill Crowley when he arrives at Fort Constantine to pick up the armor will not work. The armor disappears, but the mines do not go off.

If the Tenpenny Tower quest is done in such a way that the ghouls take over the tower, then Allistair Tenpenny will likely be dead by the time he is reached, if he lives before the quest even starts. In the event of this happening, Crowley's request to kill Tenpenny cannot be taken, though credit for his death can be. However, only 50 caps will be received due to it not being via head shot. There is a slight plot discontinuity in that the Tenpenny Tower quest can be finished, but not re-visiting the tower afterward and learning that the ghouls have taken over the building, Crowley can still be told that Allistair Tenpenny is dead.

Investigating Mister Crowley's original story will provide easy speech challenges with 7 named ghoul citizens in Underworld. Not all of them have to be completed to ask Mr. Crowley about his true intentions.

If completing this quest in a non-violent way, lying to get the full reward will result in Three Dog reporting that Crowley's targets have been murdered in his Galaxy News Radio broadcasts.

Not giving Crowley the keys makes him hostile, as well as the entire Underworld.

If Crowley is given the keys he will say that he finally has all four keys "including his", but only three are needed obtain the armor.

If the keys are delivered to Mr. Crowley and the fort is fast-traveled to within three days of doing so, he can be found in the basement extension of the bomb storage shelter, not hostile and wearing the T-51b armor and smoking. Interacting with him will only give dialogue options as if he were in Underworld. He can still be killed and looted of the armor, keys, and many other items (as everyone would comment in Underworld that he was 'preparing') without any Karma loss.

If Mister Crowley is given some of the keys (not all), they can pickpocketed back and given to him all over again. The full-price dialogue will not be available, so each key will only earn 25 caps. This can be repeated as much as desired, and incurs no Karma loss when pickpocketing evil characters. The keys are rather easy to successfully pickpocket, even with a medium Sneak skill, so it can be a way to farm extra caps.

When entering Dukov's house, hostile enemies in close proximity may follow inside.

An Enclave-controlled deathclaw may be escaped and wandering not too far away from Dukov's Place. After killing any nearby Enclave soldiers, the deathclaw (if the player has the deathclaw control scrambler) will follow the player. Upon entering Dukov's house, Dukov will kill the deathclaw.

Even if not given the keys but still taking the armor, Crowley will track the Lone Wanderer down in attempt to kill them. His death does not affect Karma.

The title is a reference to the common convention in zombie fiction that the undead can only be killed by destroying their brain. Mister Crowley himself refers to these legends. Allistair Tenpenny also mentions this if you tell him that Mr. Crowley is still alive.

The following is based on Fallout 3 cut content and has not been confirmed by canon sources.

A number of elements indicate that the prototype medic power armor was originally intended to be the armor recovered from Fort Constantine. The terminal for gaining access to the power armor lists it as "Medical Armor Prototype", while the EditorID for the prototype medic power armor is MS14PowerArmorMorphine, "MS14" being the internal EditorID of the quest.

pcps3xbox360 After completion of Operation: Anchorage!, when picking up the winterized T-51b power armor and equipping it, the trophy/achievement for this quest may suddenly become unlocked. If you drop it from your inventory and do not have a convenient game save, leave it where you dropped it and retrieve it after completing the quest. [verified]

xbox360 Mr. Crowley may appear at your Megaton house and follow you inside. When speaking with him he acts as if he's still in Underworld. However, once he exits the house and you speak to him as he exits Megaton, he begins saying, "You took what was rightfully mine," without becoming hostile. He then disappears from the game. [verified]

xbox360 He may also show up in Megaton hostile, gun drawn, but not firing. All the citizens of Megaton will ignore him. [verified]

pcps3xbox360 After accepting Allistair's offer and killing Mr. Crowley, Allistair may not have a speech option to finish the quest. If this happens, you can: [verified]

Repeatedly talk to Tenpenny and he will eventually recognize that Crowley is dead and give you your reward.

Take the T-51b power armor from Fort Constantine and complete the quest. If you do this, you will miss out on the reward for killing Crowley.

pcps3xbox360 After accepting Allistair's offer and killing Mr. Crowley, Allistair may give you a reward, but the quest will not end. It will keep telling you to collect your reward from Tenpenny. If you talk to Allistair again, he acts as though you have not even mentioned Crowley yet. The quest can be completed by going to Fort Constantine and retrieving the power armor. This can be fixed on the PC through the console by typing setstage 14ea1 100. [verified]

pcps3xbox360 If you have Bloody Mess and/or the body's head explodes, it will not be registered as a head shot, and you will not be able to receive the full 100 caps for the kill. [verified]

ps3xbox360 The quest will sometimes complete itself when switching to a different quest, granting the achievement and registering that you have killed people that you have never met. [verified]

ps3xbox360 If you kill Tenpenny, then kill Mr. Crowley, you will not fail the quest. It will tell you to talk to Tenpenny, and then to talk to Crowley, making it impossible to finish the quest. [verified]

ps3xbox360 If you have completed Operation: Anchorage, and continue until the Waters of Life quest, upon exiting Tranquility Lane, you may be informed that you completed "You Gotta Shoot 'em In the Head." [verified]

xbox360 It is possible that after completing the quest, Crowley can show up in the Mobile Crawler at Adams Air Force Base. [verified]

ps3xbox360 On his way to the Fort, Crowley may get stuck between Underworld and the Mall. This glitch can sometimes be fixed by reentering the underworld and the Ninth Circle, then exiting the museum to the mall Mr Crowley will be there. [verified]

ps3xbox360 You may be able to tell Crowley you killed Tenpenny but not have the dialogue option of saying you shot Tenpenny in the head, even if you did. [verified]

xbox360 Sometimes when you give Crowley multiple keys, then talk to him about his true motives, the speech dialog only allows you to receive non-headshot kills for 25 caps for every key afterwards, even though he promises 100 per key. [verified]

xbox360 If you acquire all keys, turn them in to Mr. Crowley to get the reward, and then kill him, you can take his items off of his corpse. However, if you accepted Tenpenny's counter offer, you will be unable to receive the reward from him. When you talk to him, there is no option to tell him that Crowley is dead, but you can do a speech check (if you haven't done it before) and earn another 200 caps. [verified]

xbox360 Giving the Winterized version of the armor to a follower such as Fawkes may cause the mission to be completed. Doing this will cause dialogue with Crowley as though you have completed the mission by taking the T-51b power armor from him. [verified]

xbox360 Killing any of Crowley's targets with the Silenced 10mm pistol does not count as a headshot kill, regardless of where you shot them. [verified]

pcps3xbox360 If you have already accepted Crowley's mission, installing Operation: Anchorage! during this mission as an add-on will show this mission as complete without any indication of its completion, and can still be done with full rewards from it. [verified]

ps3 On rare occasions, upon entering the room with the power armor, you may find the helmet on the floor while the power armor itself is still on stasis. [verified]

pcps3xbox360 If you have completed Tenpenny Tower and have the ghouls move in with the other non-ghoul residents, Roy Philips will kill Tenpenny. Causing his body to not be available to search. You will now not be able to get his key. [verified]

pcxbox360 With Broken Steel sometimes Crowley will not appear so you cannot start the quest. [verified]

ps3 After the cut scene that segues into The American Dream, you may be informed that you've completed You Gotta Shoot 'Em in the Head. You will be awarded the proper amount of experience, you will get the trophy, and the Pip-Boy will mark the quest as complete and grey it out, as with any other completed quest. The quest's objectives will also be marked as completed in your Pip-Boy.[verification needed]